The pharmaceutical industry offers a diverse array of dispensers and containers for medications. While governmental regulations require child-resistant caps on bottles and vials containing pharmaceutical products, there exists a general need in the art for a device which is not only child-resistant, but also permits access to the medicaments or other articles contained therein to persons of diminished dexterity or cognitive function.
In recent years, blister packaging has become universally popular not only for medicaments in the form of capsules, pills or lozenges, but also for various electronic and automotive parts and the like. In a conventional blister package dispenser, the articles to be dispensed are sandwiched between a layer of transparent or translucent plastic in the form of a generally outwardly extending cavity or blister cell and a rupturable or puncturable layer. Force applied to the exterior of the outwardly extending blister cell, for example by the pressure of one or more fingers or the thumb of the individual dispensing the article, is transmitted to the article contained therein which subsequently ruptures or punctures the rupturable or puncturable layer. The article may then be removed or otherwise dispensed from the blister cell.
Because the contents of a blister package are generally visible and sometimes highly colored, they can become the targets of inquisitive children who risk substantial injury and/or death if they succeed in opening the package and ingesting or mishandling the contents thereof. Accordingly, it is important to childproof such packaging by rendering it too difficult to open for children while concurrently providing a user-friendly apparatus for use by adults who may be of diminished dexterity or digital function.
Childproof or child-resistant blister packages comprise a diversity of arrangements well-known to one of ordinary skill in the art. Certain of these incorporate so-called xe2x80x9ctear-awayxe2x80x9d or xe2x80x9cpeel-awayxe2x80x9d backing strips designed to protect the contents of the blister package from contamination or unintended consumption by children. For example, U.S. Pat. No. 3,809,221 discloses a blister-type package comprising a flexible polymeric backing sheet covering a rupturable sheet of a medicament package. In such packaging, the pill or medicament cannot be forced through the rupturable sheet unless the backing sheet is first torn or peeled away. Other variations incorporating multiple xe2x80x9ctear-awayxe2x80x9d backing sheets are found in U.S. Pat. Nos. 3,503,493; 3,621,992; and 3,387,699. Additional examples of such blister packages are disclosed in, inter alia, British Patent 1,576,316;, U.S. Pat. Nos. 3,872,970; 3,905,479; 3,921,805; and 4,216,860. The disclosures of the aforementioned U.S. patents are all incorporated herein by reference.
Unfortunately, most of the aforementioned devices suffer from certain disadvantages attendant to xe2x80x9ctear-awayxe2x80x9d or xe2x80x9cpeel-awayxe2x80x9d sealing means including progressively diminished integrity of the seal, stress-induced fatigue or wear of the sealing means following repeated opening and closing of the package, and difficulty of access to persons of diminished dexterity or physical ability. The present invention is directed to an improved, child-resistant blister package device which overcomes the attendant disadvantages of the aforementioned prior art devices by providing a blister package apparatus that, optionally, but preferably, comprises a blister package retained in a housing having a dispensing aperture blocked by a substantially rigid backing sheet. The backing sheet initially occupies a position blocking the dispensing aperture of the housing. During operation of the device, pressure exerted on at least one exposed end portion of the backing sheet imparts arcuate flexure thereto, and dislocation thereof, from blocking contact with the dispensing aperture of the housing, thereby permitting an article to be dispensed therethrough. Release of pressure on an exposed end portion of the backing sheet relaxes flexure thereof and a firm block of the dispensing aperture by the backing sheet is restored. In contrast to the aforementioned prior art devices, diminished integrity of the seal and stress-induced fatigue or wear of the sealing means do not obtain from repeated manipulation of the device.